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1// Copyright 2015 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// This example shows how to use flex layout directly in the underlying render
6// tree.
7
8import 'package:flutter/rendering.dart';
9
10import 'src/solid_color_box.dart';
11
12void main() {
13  final RenderFlex table = RenderFlex(direction: Axis.vertical, textDirection: TextDirection.ltr);
14
15  void addAlignmentRow(CrossAxisAlignment crossAxisAlignment) {
16    TextStyle style = const TextStyle(color: Color(0xFF000000));
17    final RenderParagraph paragraph = RenderParagraph(
18      TextSpan(style: style, text: '$crossAxisAlignment'),
19      textDirection: TextDirection.ltr,
20    );
21    table.add(RenderPadding(child: paragraph, padding: const EdgeInsets.only(top: 20.0)));
22    final RenderFlex row = RenderFlex(crossAxisAlignment: crossAxisAlignment, textBaseline: TextBaseline.alphabetic, textDirection: TextDirection.ltr);
23    style = const TextStyle(fontSize: 15.0, color: Color(0xFF000000));
24    row.add(RenderDecoratedBox(
25      decoration: const BoxDecoration(color: Color(0x7FFFCCCC)),
26      child: RenderParagraph(
27        TextSpan(style: style, text: 'foo foo foo'),
28        textDirection: TextDirection.ltr,
29      ),
30    ));
31    style = const TextStyle(fontSize: 10.0, color: Color(0xFF000000));
32    row.add(RenderDecoratedBox(
33      decoration: const BoxDecoration(color: Color(0x7FCCFFCC)),
34      child: RenderParagraph(
35        TextSpan(style: style, text: 'foo foo foo'),
36        textDirection: TextDirection.ltr,
37      ),
38    ));
39    final RenderFlex subrow = RenderFlex(crossAxisAlignment: crossAxisAlignment, textBaseline: TextBaseline.alphabetic, textDirection: TextDirection.ltr);
40    style = const TextStyle(fontSize: 25.0, color: Color(0xFF000000));
41    subrow.add(RenderDecoratedBox(
42      decoration: const BoxDecoration(color: Color(0x7FCCCCFF)),
43      child: RenderParagraph(
44        TextSpan(style: style, text: 'foo foo foo foo'),
45        textDirection: TextDirection.ltr,
46      ),
47    ));
48    subrow.add(RenderSolidColorBox(const Color(0x7FCCFFFF), desiredSize: const Size(30.0, 40.0)));
49    row.add(subrow);
50    table.add(row);
51    final FlexParentData rowParentData = row.parentData;
52    rowParentData.flex = 1;
53  }
54
55  addAlignmentRow(CrossAxisAlignment.start);
56  addAlignmentRow(CrossAxisAlignment.end);
57  addAlignmentRow(CrossAxisAlignment.center);
58  addAlignmentRow(CrossAxisAlignment.stretch);
59  addAlignmentRow(CrossAxisAlignment.baseline);
60
61  void addJustificationRow(MainAxisAlignment justify) {
62    const TextStyle style = TextStyle(color: Color(0xFF000000));
63    final RenderParagraph paragraph = RenderParagraph(
64      TextSpan(style: style, text: '$justify'),
65      textDirection: TextDirection.ltr,
66    );
67    table.add(RenderPadding(child: paragraph, padding: const EdgeInsets.only(top: 20.0)));
68    final RenderFlex row = RenderFlex(direction: Axis.horizontal, textDirection: TextDirection.ltr);
69    row.add(RenderSolidColorBox(const Color(0xFFFFCCCC), desiredSize: const Size(80.0, 60.0)));
70    row.add(RenderSolidColorBox(const Color(0xFFCCFFCC), desiredSize: const Size(64.0, 60.0)));
71    row.add(RenderSolidColorBox(const Color(0xFFCCCCFF), desiredSize: const Size(160.0, 60.0)));
72    row.mainAxisAlignment = justify;
73    table.add(row);
74    final FlexParentData rowParentData = row.parentData;
75    rowParentData.flex = 1;
76  }
77
78  addJustificationRow(MainAxisAlignment.start);
79  addJustificationRow(MainAxisAlignment.end);
80  addJustificationRow(MainAxisAlignment.center);
81  addJustificationRow(MainAxisAlignment.spaceBetween);
82  addJustificationRow(MainAxisAlignment.spaceAround);
83
84  final RenderDecoratedBox root = RenderDecoratedBox(
85    decoration: const BoxDecoration(color: Color(0xFFFFFFFF)),
86    child: RenderPadding(child: table, padding: const EdgeInsets.symmetric(vertical: 50.0)),
87  );
88
89  RenderingFlutterBinding(root: root);
90}
91